Accuracy vs. Precision is a theory used in chemistry, presented by Mrs. Couling. Scientists aim for measurements to be both accurate and precise.

Accuracy

Accuracy refers to the measure of "rightness". By definition, accurate means "capable of providing a correct reading or measurement". A measurement is accurate if it correctly reflects the size of the thing being measured. Accuracy refers to how closely a measured value agrees with the correct value.

Accuracy is correctness.

Precision

Precision refers to the measure of "exactness". By definition, precise means "repeatable, reliable, getting the same measurement each time". Precision refers to how closely individual measurements agree with each other.

Precision is repeatability.